1. Field of the Invention
This invention relates to devices for intercommunication between coupled vehicles in which passengers are able to walk freely, in particular railway cars, road vehicles such as, for example, articulated buses or trolley buses or even specialized vehicles such as passenger bridges of the type used in large airports.
For the sake of enhanced simplicity, reference will be made almost exclusively in the following description to railway passenger cars. However, it would clearly not constitute any departure from the scope of this invention if the term "railway car" as used hereinafter were to be replaced by the term "vehicle" as interpreted in the sense defined earlier.
2. Description of the Prior Art
As a general rule, an intercommunication device of a known type used in railway rolling stock and referred-to as a "concertina vestibule" consists of a bridge-type unit having a structural framework equipped with a bellows or equivalent flexible structure, this unit being often completed by side shields. These devices are relatively complicated, not impervious to outside air and are frequently unattractive in general appearance.